Department of Psychiatry and Psychotherapy, Psychiatric Services Aargau AG, Brugg-Windisch, Switzerland.
Department of Inpatient Psychotherapy and Crisis Intervention, University Clinic for Psychiatry, Psychotherapy, and Psychosomatics, Christian Doppler Clinic, Paracelsus Medical University, Salzburg, Austria; Department of Clinical Psychology, Christian Doppler Clinic, University Clinic for Psychiatry, Psychotherapy, and Psychosomatics, Paracelsus Medical University, Salzburg, Austria.
J Affect Disord. 2024 Dec 15;367:598-605. doi: 10.1016/j.jad.2024.08.239. Epub 2024 Sep 5.
Suicide remains a significant public health concern worldwide. Ecological studies reported decreased suicide rates with higher levels of trace lithium levels in drinking water, leading to suggestions of adding lithium to drinking water as a preventative anti-suicide strategy. However, the evidence remains inconclusive, and thus more data are needed.
This pre-registered study analyzed the association between lithium concentrations in drinking water and suicide rates across 1043 municipalities in Switzerland between 1981 and 2021. We used bivariate correlation analysis, ordinary regression models, and spatial regression models, while accounting for potential confounding variables.
There were no significant associations between lithium levels in drinking water and suicide rates, as determined by correlation analysis (r = -0.03, 95 % CI -0.09-0.03, p = 0.33), and by multivariable ordinary and spatial regression models.
The correlation between levels of lithium in tap water and the serum of individuals is unknown and ecological studies are inherently limited to establish a causal association.
The null finding in our study adds to the ongoing debate on the effectiveness of trace lithium in drinking water as a public health intervention for suicide prevention, indicating that calls for lithium supplementation are still premature. These findings highlight the need for further research with transparent and replicable methodologies to clarify the potential role of lithium in suicide prevention.
自杀仍是全球范围内一个重大的公共卫生关注点。生态研究报告称，饮用水中痕量锂水平较高与自杀率降低有关，这促使人们提出在饮用水中添加锂作为预防自杀的策略。然而，证据仍然不确定，因此需要更多的数据。
本预先注册的研究分析了 1981 年至 2021 年期间瑞士 1043 个市镇的饮用水中锂浓度与自杀率之间的关系。我们使用了双变量相关分析、普通回归模型和空间回归模型，同时考虑了潜在的混杂变量。
相关性分析（r = -0.03，95%置信区间-0.09 至 0.03，p = 0.33）和多变量普通回归和空间回归模型均表明，饮用水中的锂水平与自杀率之间没有显著关联。
我们不知道自来水中的锂水平与个体血清中的锂水平之间的相关性，且生态研究本身受到固有限制，无法确定因果关系。
本研究的阴性结果增加了关于饮用水中痕量锂作为预防自杀的公共卫生干预措施的有效性的持续争论，表明呼吁补充锂仍为时过早。这些发现强调需要采用透明且可复制的方法进一步研究，以阐明锂在预防自杀中的潜在作用。
